Following the okara quiche experiment posted above, I tried out a few "okara sweets" such as cookies and pound cakes. And there were good ones like "okara and azuki cake" and "okara and fruit pound cake" (both in Japanese). They have favorable reviews and I did like the taste of those cakes. At the first bite, I agreed with some of the reviews that said "I like the texture of okara cake better than that of regular cakes made with flour. It's moister and fluffier." However, after chewing several times, I went, "Wait a minute..." When it was about time for regular cake to melt and disappear, I felt plenty of fiber still filling up my mouth and I had to make conscious effort to swallow it. It wasn't terribly unpleasant, but I wasn't too crazy about that.
Then I found some cookie recipes that called for powdered okara instead of fresh okara. These days "okara powder" is available as a baking ingredients in Japan, and actually you can make something very close at home.
Homemade Okara powder (Instruction here in Japanese)
To make this, you spread okara on lined baking sheet and bake it in the oven and then mill it in a food processor. The recipe says that this okara powder can be frozen and keeps for about a month.
I thought that with this powder, I would have less problem of the fiber remaining in the mouth, and I was right. This okara cookie recipe (Japanese) is my current favorite, with a texture somewhat similar to coarse shortbread. But I'm still working on it to make it lighter and crunchier. (I'm thinking about using maple syrup so that the dough would come together more easily and adding just a little baking powder to make it lighter.)
The original recipe didn't use black sesame seeds, but I like it this way.
AHHHHHHHHHHHH I shouldn't be doing this. I've got to pack, and clean! :O